I'm not a tech guy by any means but this latest brainchild of Silicon Valley hot shot Elon Musk is way kewl.

It's called a "Hyperloop" and will be designed to carry people faster than the speed of sound between cities. If it were anyone else besides Musk, the whole idea could be filed away as fantastical nonsense. But Musk's dreams include a viable commercial spacecraft that has already delivered supplies to the space station.

The Telegraph:

Mr Musk will not be patenting the design and it will be "open source", meaning anyone can modify it, or try to build it.

The fevered speculation about what it would actually look like has ranged from wild theories on Star Trek-style teleportation to more achievable ones involving cars being pushed through vacuum sealed tunnels using magnets.

Mr Musk has denied it will be a so-called "vactrain", a concept that is already being pursued by a company in Colorado. His idea "does involve a tube, but not a vacuum tube", he said, adding: "Not frictionless, but very low friction."

In recent weeks a large part of the mystery appeared to have been solved. A technology enthusiast in Canada called John Gardi published a diagram of how the Hyperloop might work. He went on to ask Mr Musk on Twitter: "Can you give me some basic clues? What diameter of tube so I can start designing stations and throughways?"

To his extreme surprise Mr Musk replied: "Your guess is the closest I've seen anyone guess so far. Pod diameter probably around 2m."

Mr Gardi, who describes himself modestly as a "tinkerer", came up with a tunnel 9ft in diameter, raised above the ground on pylons. His tube could be made from materials already used for sewer pipes. It would form a continuous loop between two destination points. Giant turbines would blast a stream of air into the tube. The two-metre wide pods, carrying people, would be moved by a rail gun - a tube that uses magnets to accelerate material passing along it.

As they approach their journey's end they would be routed out of the air stream and slowed down using a magnetic braking system.

In an extensive analysis published on the website Motherboard, Mr Gardi concluded: "I believe that Hyperloop is merely a modern day version of the pneumatic tubes used in banks, stores, and industry to move money and small items over long distances or to other floors of a building.

"They've been around for over a century, though not so much these days. One reason I think Hyperloop is simpler than folks think is that Elon Musk has resurrected another technology from the depths of time, one that was a contender once, too - the electric car!"

It sounds great - but what's the pricetag Elon? Not just the system but the infrastructure has got to cost tens of billions of dollars.

We've already got a boondoggle in high speed rail, but thanks anyway Mr. Musk. We'll get back to you on this one.